The last option is definitely possible. The Script step: Save As PDF has an "append" option that can append the PDF being generated to the end of an existing PDF file. The added PDF pages will start with a new page.
For the first step in getting a Saved PDF see this thread: Found Sets to PDF with unique file names
I know I posted this in another thread you also started, but am including it here in case someone finds this thread by searching the forum...
sound good, Phil. The only missing piece of the equation being if it would be possible to generate the PDF out of an existing layout, say from within a button and via a script, or do I need to format the report with variables ? I saw a "Save records as PDF" script step, but that would be unformatted, right ?
Save Records as PDF produces the exact same result as choosing "Print" from the file menu, but the results are produced as an electronic file in PDF format. The design of your current layout and it's current found set of records will determine the results produced.